This invention relates to a structure mounted on wheels for launching a spacecraft horizontally and, more particularly, the invention is concerned with providing a ground accelerator having multiple point support for the launch vehicle, ground mobility including power and steering.
Highly loaded spacecraft with a full fuel load when sitting on the ground in a horizontal position place unusual loadings on the structure concentrated at the landing gear attach points. Once airborne, these loadings are distributed throughout the structure. Thus, this ground loaded condition imposes a penalty on the structure not necessary for flight.
The landing gear must be designed for the maximum takeoff weight rather than the landing weight which, in the case of the single-stage-to-orbit space vehicle, is a ratio of approximately 10 to 1; this is a direct weight penalty on the landing gear and attach structure.
The accelerator requirements to achieve a safe takeoff speed within the constraints of runway length indicate a high thrust level desirability, higher than necessary for flight. This high thrust also requires a high fuel flow with a significant portion of the fuel capacity used before flight is achieved.